Dual suspension and seal



May 12, 1964 c P LANMON' n 3,132,379

DUAL. SUSPENSION AND SEAL Original Filed April 4, 1955 4 Sheets-Sheet 1 C P 1 0/7/7700 ZZ' INVENTOR.

ATTORNEY y 2, 1964 c P LANMON 11 3,132,879

DUAL SUSPENSION'AND SEAL Original Filed April 4, 1955 4 Sheets-Sheet 4 CU Zc7/7/770/7,I

IN V EN TOR.

ATTORNEY United States Patent Ofl ice 3,132,879 Patented May 12, 1964 3 Claims. (Cl. 285-437) This invention pertains to well completion apparatus, and more particularly to such apparatus at the surface of the earth for a parallel string dual completion, that is, for a completion in which the oil or gas may be produced from two diflerent zones and in which two strings of tubing disposed parallel side by side extend respectively from the two production zones to the surface, as distinguished from an ordinary dual completion in which there is but one tubing string and one zone is produced through the annulus between the tubing and casing.

It is desirable to provide in such an apparatus a separate flow passage associated with each string of tubing extending in a straight line all the way to the top of the tree whereby all the usual operations carried on ugh the tubing during the life of a well can be carried on satisfactorily through each tubing to its particular production zone. It is also desirable in such an apparatus, when there is high pressure in both production zones, that each tubing string and associated flow passage be separated from the outside of the apparatus by high pressure resisting walls up to and through a master valve whereby blowout protection is assured. These two requirements present difficult problems with reference to the sealing and suspension of the two tubings and the surface completion equipment.

This application is a division of my prior copending application Ser. No. 498,791, filed April 4, 1955, now abandoned.

A principal object of the invention is to provide a tubing suspension for such an apparatus which will be strong and reliable.

Another object of the invention is to provide a connection between two parallel pipes and a body having two flow passages therethrough, such as a dual valve or dual T, especially adapted for use where the pipes extend from a casing head, adapter flange, valve body, or other supporting means or protecting housing having a flange adapted to be coupled to a similar flange on the dual flow passage valve, T, or other body.

Another object of the invention is to provide a dual tubing head seal for the annulus or space between the tubing strings and the tubing head.

Other objects and advantages of the invention will appear from the following description of preferred embodiments thereof, reference being had to the accompanying drawings wherein FIGURES 1 and 2 are side elevations, partly in section, of the lower and upper portions respectively of a tree according to one form of the invention.

FIGURES 3, 4 and 5 are a side elevation and horizontal sections through a seal for the annulus in the tubing head;

FIGURE 6 is a view similar to FIGURE 1 showing a modification.

slidable within bore 73 and centers the coupling.

Referring now to FIGURE 1, there is shown the lower section of a well completion apparatus comprising a tubing head 10 adapted to be supported on and connected to a casing head (not shown) by flange 11. The upper end of a casing 13 is sealed within the lower end of the tubing head by seal 14. This seal is described more fully in United States patent application Serial Number 336,958, filed February 16, 1953, by Andrew C. Oden and I. C. Shuptrine, entitled Interchangeable Tubing Head Seal and Casing Hold-Down and Tool Guide.

The tubing head is provided with outlet port 15 to which a valve 16 is connected to control flow from the casing annulus.

The upper end of tubing head 10 is provided with a tapered bowl 17 within which is seated a dual bore wrap around tubing seal 18 which is shown in detail in FIG- URES 3, 4, and 5. As there shown the seal comprises a ring of sealing material 21 having a conical external surface 22 and two parallel cylindrical passages or ports 23, 24 centered on a vertical diametral plane therethrough. The seal ring is split vertically at 25 between outer surface 22 and port 23 and at 26 between ports 23 and 24, the material between port 24 and surface 22 providing a hinge since the ring is made of rubber or similar material that is flexible and that makes a good seal.

Ring 21 is held between upper and lower split metal rings 31, 32 to which it is vulcanized or in other manner secured. Ring 31 has a lower cylindrical outer portion 33 and an upper conical portion 34. It has two ports 35, 36 therethrough aligned with ports 23, 24. Ring 31 is split at 37, 38, 39 in alignment with splits 25, 26. The two halves of ring 31 are connected at one side by hinge 40 and at the other by latch 41. Ring 32 has a tapered outer surface 42 and two ports aligned with ports 24 and 25 and is split clear across on a vertical diametral plane aligned with splits 25, 26. It will be noted that seal 18 is split along a vertical diametral plane defined by the axes of the vertical passages therethrough.

Referring again to FIGURE 1, two sections of tubing 51, 52, constituting the upper portions of two tubing strings, extend up through seal 18. The upper ends of these tubing sections are upset at 53, 54 to provide material for threads 55, 56. In order that seal 18 may be as close as possible to the ends of the tubing sections, the ports 35, 36 are counterbored to provide enlarged portions 57, 58 into which the upset ends 53, 54 can freely enter. Seal 18 is locked in place and compressed by screws such as 59 passing through flange 68 of the tubing head and engaging with conical surface 34.

Mounted on flange is a suspension ring 70, which is sealed to flange 60 by a steel ring gasket 71. Ring 70 has two bores 72, '73 centered on a diametral plane and adapted to be aligned with tubing sections 51, 52. Bore 77 is threaded at its lower end to receive thread 55 of tubing section 51 and at its upper end toreceive tubing nipple 80.

Bore 73 is provided with an inturned flange 81 at its lower end to support a pipe coupling 82 Which'is threaded at its lower end to receive thread 56 of tubing section 52 and at its upper end to receive tubing nipple 83. The exterior of coupling 82 has a smaller diameter than bore 73 except for a flange 84 at its lower end which is A packing 85 between bore 73 and coupling 82 is compressed by a ring 86 screwed into a threaded counterbore in the upper end of bore 73.

The above described connection of tubing sections 51, 52 to suspension ring 70 enables one of the tubing sections to be connected to the ring by a simple threaded connection which occupies a minimum of radial space. The other connection cannot be the same since the ring cannot be rotated to couple it to the other tubing section once it has been screwed onto the first tubing section and since the long tubing string cannot easily be rotated. The second tubing string is therefore hung on a coupling and packed off, providing a suspension which does not require rotation of either the tubing or the suspension ring. Although this type of suspension requires a larger radial extent than the threaded suspension, there is still suflicient metal between the two suspensions to provide adequate strength, since the simple threaded connection does not take up much room, extending radially only the depth of the thread.

Mounted on top of ring 70 is dual valr e 911 which has a lower flange 91 sealed to the ring 71) by a steel ring gasket 92. Flanges 1 and 6b and ring '70 are held together by through bolts such as 93. If valve flange 91 is of smaller diameter than tubing head flange 60, an adapter flange may be substituted for ring 70.

The dual valve 91 may be of any desired type. Preferably it comprises two automatic plastic sealed gate valves of the type described in United States Patents 2,317,657 issued April 27, 1943, entitled Conduit Valve and 2,433,638 issued December 30, 1947, entitled Automatic Lubricate Valve, the two valves being disposed in a unitary housing as shown in FIGURES 1 and 2 hereof.

On top of valve 90 is disposed a dual T 1110, the lower flange of the T being sealed to the upper flange of valve 911 by ring 161 and held in place by through bolts 1112. On top of T 100 is another dual valve 103 similarly sealed and bolted, and the top of valve 103 covered with a protecting plate 104 sealed and bolted thereto in like manner.

In order to provide connections between the dual bores of ring 70, valve 90, T 100, and valve 1113, there are provided connecting means comprising pipes and seals which are the same in each case so that only the connection between T 100 and valve 163 will be described. It comprises two pipes 111), 111 screwed into counterbores 112, 113 in the top of the T. The pipes extend up into single counter bore 114 in the bottom flange of valve 103 and thence into two smaller counterbores 115, 116 in the body of the valve and finally into two still smaller counterbores 117, 118, all concentric with flow passages 119, 120 of the valve. Packing 121, 122 in counterbores 115, 116 and around the pipes 110, 111, is adapted to be compressed by gland rings 123, 124, which in turn are pushed upwardly by dual bore compression ring 125, which is forced upwardly by a plurality of screws 126 disposed around the periphery of the valve flange. It will be seen that this type of connection allows the upper unit, that is, valve 103, to be placed on top of the lower unit, that is, T 106, and thereafter the two pipes sealed to the two bores of valve 103 by tightening the lock screws 126. If desired, the connection could be reversed by screwing the pipes into the upper member and telescoping and packing them in the lower member.

Referring now to FIGURE 6 there is shown a modification of the apparatus shown in FIGURE 1. The apparatus is generally similar in that it includes the same tubing head 10 having a flange 11 resting on top of a casing head 12 in which a casing 13 is suspended. Also, the upper end of the casing is sealed in the tubing head at 14. The principal difference lies in the omission of suspension ring 70, the valve 90 being disposed directly on top of the tubing head. Instead of suspending the tubings 151 and 152 in a suspension ring, they are suspended in a hanger 153.

The hanger 153 is of circular cross-section and has a tapered or conical seat 154 adapted to rest on tapered bowl 17 of the tubing head. A plurality of packing rings 155, 156 are compressed and the hanger is held in place by means of lock screws 59, the same as seal 18 of the FIGURE 1 embodiment is compressed and held in place.

The hanger 153 is provided with two passages therethrough, similar to seal 18. However, one of the passages is threaded at its upper and lower ends to receive the top of tubing 151 and the lower end of pipe nipple 161. The other passage 162 is provided with a series of counterbores to receive coupling screwed onto the top of tubing 152, packing 171 around the coupling, and compression ring 172 on top of the packing, the counterbore for ring 172 and the ring itself being screw threaded.

A pipe nipple 173 is screwed into the top of coupling 170. The upper ends of pipes 161 and 173 may be sealed within valve 90 by means the same as shown in FIGURE 1 or they can be sealed by the modified arrangement shown in which a single dual bore packing having an outer diameter the same as that of dual bore compression ring 125 iscompressed against the lower face 131 of the body of valve 90, being held within counterbore 182. Lock screws 126 force ring 125 upwardly the same as in the FIGURE 1 embodiment.

Comparing the embodiments of FIGURES l and 6, it will be noted that in both embodiments the suspension means, ring or hanger is screwed onto one of the tubings by rotating the suspension means around the tubing and the other tubing string is hung in the suspension means on a coupling. This coupling is preferably of larger diameter than the couplings used in the rest of the tubing string so that the tubing can be run through the suspension means.

Differences between the FIGURES 1 and 6 embodiments appear in comparing the setting of the tubing strings. With the FIGURE 1 embodiment, the first string of tubing is run through the usual blowout preventers mounted on top of the tubing head and a temporary dual bore hanger similar to the lower plate of the seal is wrapped around the tubing and dropped through the preventers into the bowl of the tubing head. That string of tubing is then suspended by a coupling resting on top of the hanger. Then the other string of tubing is run through the preventers and an enlarged bore in the hanger and tinally suspended in the hanger by an enlarged coupling. The preventers are then removed and the first of tubing is lifted out of the hanger and the suspension ring screwed thereon. Then the other tubing string is lifted and run through the adapter flange and connected therein. The temporary hanger is removed from the bowl of the tubing head and the seal is substituted therefor and the suspension ring is placed on top of the tubing head and the rest of the tree assembled thereon.

In the FIGURE 6 embodiment the temporary hanger is eliminated. After the first string of tubing is run the permanent hanger is screwed onto the tubing and lowered into the bowl. Then the second string of tubing is run through the preventers and the enlarged opening of the hanger and finally an enlarged coupling is seated in the hanger. The well can thus be placed under the full control before the preventers are removed and the rest of the tree assembled on top of the tubing head. With this construction when the well is to be reworked the tree can be removed clear down to the tubing head and workover preventers placed on top and then the strings can be pulled through the preventers.

While preferred embodiments of the invention have been shown and described, many modifications thereof can be made by one skilled in the art without departing from the spirit of the invention, and it is desired to protect by Letters Patent all forms of the invention falling within the scope of the following claims.

I claim:

1. In a dual completion apparatus including a well head assembly having a hanger device supported thereby for supporting a pair of parallel well pipes, a dual bore seal comprising upper and lower metal members having a layer of rubber like sealing material secured therebetween and contacting said well head assembly around its periphery, said seal having two diametrically aligned passages therethrough transverse to said layer of sealing material and metal members each for receiving one of said well pipes therethrough, a diametrical split extending all the way across said metal members and from one side of said layer of sealing material to the adjacent one of said passages and between said passages, said well head assembly having upwardly facing support means and said lower metal member being supported thereon, and means for urging one of said metal members toward the other to actuate the seal.

2. Combination of claim 1, including hinged connection means for said upper and lower metal members at the end of said diametrical split opposite said one side of said layer of sealing material, and including releasable latch means for said upper and lower metal members at the end of said diametrical split at said one side of said layer of sealing material.

6 3. Combination of claim 1, said passages having counterbores therearound at their upper ends terminating downwardly above the lower surface of said upper metal member to receive the upper upset end of a string of tubing rested on said upper metal member for support of the string of tubing.

References Cited in the file of this patent UNITED STATES PATENTS 1,790,904 Creighton Feb. 3, 1931 1,851,940 Williams Mar. 29, 1932 2,001,946 Tschappat May 21, 1935 2,086,431 Penick et a1. July 6, 1937 2,335,355 Penick et a1. Nov. 30, 1943 2,735,697. Zanin Feb. 21, 1956 2,786,417 Lung Mar. 26, 1957 2,850,099 Brown Sept. 2, 1958 

1. IN A DUAL COMPLETION APPARATUS INCLUDING A WELL HEAD ASSEMBLY HAVING A HANGER DEVICE SUPPORTED THEREBY FOR SUPPORTING A PAIR OF PARALLEL WELL PIPES, A DUAL BORE SEAL COMPRISING UPPER AND LOWER METAL MEMBERS HAVING A LAYER OF RUBBER LIKE SEALING MATERIAL SECURED THEREBETWEEN AND CONTACTING SAID WELL HEAD ASSEMBLY AROUND ITS PERIPHERY, SAID SEAL HAVING TWO DIAMETRICALLY ALIGNED PASSAGES THERETHROUGH TRANSVERSE TO SAID LAYER OF SEALING MATERIAL AND METAL MEMBERS EACH FOR RECEIVING ONE OF SAID 